'Stargate SG-1' spinoff debuts

Joe Flanigan stars in this spinoff and companion to "Stargate SG-1." Humans discover yet another portal left behind by the Stargate builders, which will make for adventures in even more galaxies.

10 p.m. on HBO

"Da Ali G Show'

Yo! A new season of subversive comedy by the chameleonlike Sacha Baron Cohen begins next week. So HBO is giving viewers a chance to refresh their memories with six back-to-back episodes from last season.